<template>
  <el-container class="home-container">
    <!-- 头部区域 -->
    <el-header>
      <div>
        <img src="../assets/tow.png" alt />
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logoout">退出</el-button>
    </el-header>
    <!-- 页面主体区域 -->
    <el-container>
      <!-- 侧边栏 -->
      <el-aside :width="isCollapse ?'64px':'200px'">
        <!-- 折叠菜单栏 -->
        <div class="toggle-button" @click="toggleCollapse" :style="isCollapse ?'color:#000000':'color:#ffffff'">|||</div>
        <!-- 侧边栏菜单区域
        :router="true"  开启路由跳转
        -->
        <el-menu
          background-color="#333744"
          text-color="#fff"
          active-text-color="#409EFF"
          unique-opened
          :collapse="isCollapse"
          :collapse-transition="false"
          :router="true"
          :default-active="activePath"
        >
          <!-- 一级菜单 -->
          <!-- index动态绑定，应为index只接受字符串所以+''装换成字符串 -->
          <el-submenu v-for="item in menulist" :key="item.id" :index="item.id+''">
            <!-- 一级菜单模板 -->
            <template slot="title">
              <i :class="iconsObj[item.id]"></i>
              <span>{{item.authName}}</span>
            </template>
            <!-- 二级菜单 -->
            <el-menu-item v-for="subItem in item.children" :key="subItem.id" :index="'/'+subItem.path" @click="saveNavState('/'+subItem.path)">
              <!-- 二级菜单模板区 -->
              <template slot="title">
                <i class="el-icon-menu"></i>
                <span>{{subItem.authName}}</span>
              </template>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>
      <!-- 主体内容 -->
      <el-main>
        <!-- 路由占位符 -->
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  data() {
    return {
      // 侧边栏菜单数据
      menulist: [],
      iconsObj: {
        '125': 'iconfont icon-users',
        '103': 'iconfont icon-tijikongjian',
        '101': 'iconfont icon-shangpin',
        '102': 'iconfont icon-danju',
        '145': 'iconfont icon-baobiao'
      },
      // 是否折叠
      isCollapse: false,
      // 储存菜单栏跳转的路由,被激活的链接地址
      activePath:''
    }
  },
  // 在页面渲染的时候发送求获取页面菜单数据
  created() {
    this.getMenuList()
    // 将获取到的值
    this.activePath=window.sessionStorage.getItem('activePath')
  },
  methods: {
    logoout() {
      window.sessionStorage.clear()
      this.$router.push('/login')
    },
    async getMenuList() {
      const { data: res } = await this.$http.get('menus')
      // console.log(res)
      // 将获取到的数据立即挂载到组件的data中方便使用
      if (res.meta.status !== 200) return this.$message.error(res.meta.msg)
      this.menulist = res.data
    },
    // 点击按钮切换菜单折叠
    toggleCollapse() {
      this.isCollapse = !this.isCollapse
    },
    // 保存链接的激活状态
    saveNavState(activePath){
      window.sessionStorage.setItem('activePath',activePath)
      this.activePath=activePath
    }
  }
}
</script>

<style lang="less" scoped>
.home-container {
  height: 100%;
}
.el-header {
  background-color: #373d41;
  display: flex;
  justify-content: space-between;
  padding-left: 0;
  align-items: center;
  color: #ffffff;
  font-size: 20px;
  > div {
    display: flex;
    align-items: center;
    span {
      margin-left: 15px;
    }
    img {
      width: 50px;
      height: 50px;
      border-radius: 50%;
    }
  }
}

.el-aside {
  background-color: #333744;
  .el-menu {
    border-right: none;
  }
}
.el-main {
  background-color: #eaedf1;
}
.iconfont {
  margin-right: 10px;
}
.toggle-button {
  background-color: #4a5064;
  font-size: 10px;
  line-height: 24px;
  text-align: center;
  // 字体间距
  letter-spacing: 0.2em;
  cursor: pointer;
}
</style>
